In the closed water areas such as the three major bays (i.e., Tokyo Bay, Ise Bay and Osaka Bay) and other designated lakes and reservoirs, water pollution by eutrophication is a serious problem. To create good water environments for life to inhabit, it is essential to try to steadily reduce non-sewer pollutant loads as well as to keep improving sewerage. Furthermore, it is necessary to promote the creation and preservation of fine waterfront spaces inside urban areas. JIWET has been carrying out joint research for the creation of a good social environment and working on the establishment of a sound water circulation system and good water environments.

Joint research already conducted

「Study on reduction of pollutant loads from non-point source in urban area」、
「Investigation of chemistry substance inflow/outflow actual condition ]of a sewer」
「Investigation research on the aquatic life living thing influence of a sewer」
etc.

Recent research

「Study and Research to Review Collaborative Measures for Water Quality Improvement of Closed Water Body」
「Survey Research of Risk of Inflows of Trace Chemical Substances and Other Disturbancesto Water Quality」
etc.